           (let [[a b] (first q)]
             (cond
               (empty? q)
-              [M src2img]
+              [op src2img]
               
               (nil? b)
               nil

             IEdge
             PeriodicGraph$CoverNode Morphism Morphism$NoSuchMorphismException)
           (org.gavrog.joss.pgraphs.io Net)
           (org.gavrog.joss.geometry Operator Vector)
           (org.gavrog.jane.compounds Matrix)
           (org.gavrog.jane.numbers Whole)))


      (->> bases
        (map #(symmetry-from-base-pair net (first bases) % sigs))
        (filter identity)))))

(defn spacegroup [net]
  (SpaceGroup. (.getDimension net) (map first (symmetries net))))
